The two half-witted private detectives Dick and Gus are asked to investigate the disappearance and possible murder of her wealthy grandfather Jonas Morton. The duo encounter houseguest Mr. Grooch and his two assistants, who are behind the goings-on, and plotting to steal the Morton fortune. Creepy butler Jarvis also seems to have an ulterior motive. Dick and Gus' presence is not appreciated, and they find themselves the targets of poison, gunfire, and an electrifying death trap.